Devices are known for packaging and dispensing a fluid substance that comprise a container for containing the substance and an associated pump, the pump having a pump chamber into which the substance is taken before being delivered to the outside.
The pump has intake valve-forming means and delivery valve-forming means, respectively upstream and downstream from the pump chamber. The pressure required for expelling the substance from the device is obtained by means of a control rod that is movable in the pump chamber. A dispenser endpiece, such as a pushbutton fitted with a nozzle, is fixed to the control rod before the container is filled.
When a user presses on the dispenser endpiece, the control rod is pressed down into the pump body and reduces the volume of the pump chamber, causing a predetermined quantity of substance to be dispensed.
When the user releases the dispenser endpiece, the control rod is returned to its initial position by a spring. This return movement of the control rod is accompanied by an increase in the volume of the pump chamber. The delivery valve-forming means are organized to prevent the substance contained in the dispenser endpiece from returning back into the pump chamber, and also to prevent air penetrating therein. The intake valve-forming means opens while the control rod is returning so as to enable the substance contained in the container to be drawn into the pump chamber.
The container can be constituted by a deformable flexible bag which shrinks as the substance is dispensed, or in a variant it may be formed by a cylindrical wall fitted with a moving bottom, e.g. constituted by a piston capable of sliding therein, or in a variant constituted by a membrane which deforms to occupy the space left empty inside the container by the substance which has been dispensed.
In known packaging and dispensing devices as outlined above, the container can be filled by a vacuum-filling process consisting of establishing suction in the container and then putting the container into communication with a source of the substance so that the substance is drawn into the container.
Such a filling process has the particular advantages of increasing the number of containers filled during production and of avoiding the substance oxidizing on coming into contact with air.
The dispenser endpiece is mounted on the control rod by forcing the control rod into an appropriate housing in the dispenser endpiece, such that the control rod is pushed into the pump body until it comes into abutment at the end of a push-in stroke.
Tests have shown that when the dispenser endpiece is mounted on the control rod after the container has been vacuum-filled, then pushing in the control rod causes a certain quantity of substance to be expelled. This gives rise to dirtying of the substance and increases the risk that any substance contained in the outlet channel of the dispenser endpiece will become degraded on contact with air. This also possibly risks even the outlet channel becoming blocked once the substance has dried.
There also exists a need for packaging and dispensing devices that have two independent containers and two pumps for simultaneously dispensing two substances that are stored separately in each of the containers.
Mounting a common dispenser endpiece on the control rods of the two pumps after the containers have been vacuum-filled would give rise to the above-mentioned drawbacks, while mounting the dispenser endpiece before the containers are filled makes the device more complicated to manufacture.
The present invention seeks in particular to enable the dispenser endpiece to be mounted on the control rod(s) of the pump(s) after vacuum-filling the container(s), but without the drawbacks mentioned above.
According to the invention, this is achieved by the fact that the packaging and dispensing device includes anti-vacuum valve-forming means organized to isolate the pump chamber(s) of the pump(s) from the inside(s) of the associated container(s) when a vacuum is established therein for filling purposes.
Thus, by means of the invention, a vacuum is not established in the pump chamber when the air initially present in the associated container is drawn out, such that when the container is put into communication with the source of substance, only the container is filled and not the pump chamber.
As a result, when the dispenser endpiece is subsequently fixed on the control rod(s) and the control rod(s) is/are pushed into the pump body(ies), no substance flows out through the dispenser endpiece.
By means of the invention, the dispenser endpiece therefore remains substantially free of substance during storage, and any risk of dirtying, degradation, or drying of the substance is avoided.
In other words, the invention makes it possible to avoid untimely dispensing of a small quantity of substance when the dispenser endpiece is put into place on the control rod(s).
The invention makes it possible in particular to mount two pumps each fitted with a respective container constituted by a flexible bag inside a case, and then fitting a cover on the case to serve both as an actuator for the pump control rods and to dispense the mixture of substances contained in the containers.
The invention is also advantageous when the dispenser endpiece is already fixed on a control rod before the container is filled.
Under such circumstances, any accidental thrust on the dispenser endpiece is then avoided during boxing or transportation, for example, so no substance flows out from the dispenser endpiece.
In known pumps, the intake valve-forming means are constituted by a ball, which therefore provides sealing only when the pump is used in a predetermined position, e.g. head-up.
The anti-vacuum valve-forming means of the invention are preferably capable of providing sealed closure in any position, thereby increasing the number of ways in which the pump can be used.
In a particular embodiment, the anti-vacuum valve-forming means form an integral portion of the pump and also act as the intake valve, enabling the substance contained in the container to be drawn into the pump chamber while preventing it from returning when the control rod is pushed in.
In a variant embodiment, the anti-vacuum valve-forming means are fitted to the pump, which is manufactured separately and may be constituted by a prior art pump that is unmodified or that has been subjected to modifications that are minor and not expensive.
By way of example, the pump can be of the type having a valve that is constituted by a ball and/or a control rod engaged with a return spring.
In another embodiment, the anti-vacuum valve-forming means comprise a support piece secured to the container with the pump being fixed thereto.
In another variant, the anti-vacuum valve-forming means are secured to the container.
The invention also provides a method of manufacturing a device for packaging and dispensing at least one fluid substance, said device having at least one container for containing a substance and a pump for dispensing it, the pump having a pump chamber into which, in operation of the pump, the substance is drawn prior to being delivered to the outside, the method comprising the steps consisting in:
assembling together the pump, the container, and anti-vacuum valve-forming means, the container being suitable for communicating via a first opening with the pump chamber via the anti-vacuum valve-forming means;
evacuating the inside of the container via a second opening thereof, the anti-vacuum valve-forming means isolating the container from the pump chamber during the evacuation step;
filling the container by causing it to communicate via said second opening with a source of substance; and
closing said second opening.
The invention also provides a method of manufacturing a packaging and dispenser device having two containers for separately containing respective substances, and two pumps respectively associated with said containers for dispensing said substances simultaneously, each of the pumps having a pump chamber into which, during operation of the pump, the substance is drawn prior to being delivered to the outside, the method comprising the steps consisting in:
assembling each pump fitted with anti-vacuum valve-forming means to the associated container;
filling each container separately by a vacuum-filling process;
inserting both pumps and the associated containers in a case; and
fitting the case with a dispenser endpiece common to both pumps.